Hi Simon, On Sun, Nov 20, 2016 at 4:25 AM, Simon Glass <[email protected]> wrote: > Add a new CONFIG_X86_64 option which will eventually cause U-Boot to be > built as a 64-bit application, with SPL doing the 16/32-bit init. > > Signed-off-by: Simon Glass <[email protected]> > --- > > Changes in v2: None > > arch/x86/Kconfig | 46 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 46 insertions(+) >
Reviewed-by: Bin Meng <[email protected]> One nits below: > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 0884af2..5db8f13 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -5,6 +5,52 @@ config SYS_ARCH > default "x86" > > choice > + prompt "Run U-Boot in 32/64-bit mode" > + default X86_RUN_32BIT > + help > + U-Boot can be built as a 32-bit binary which runs in 32-bit mode > + even on 64-bit machines. In this case SPL is not used, and U-Boot > + runs directly from the reset vector (via 16-bit start-up). > + > + Alternatively it can be run as a 64-bit binary, thus requiring a > + 64-bit machine. In this case SPL runs in 32-bit mode (via 16-bit > + start-up) then jumps to U-Boot in 64-bit mode. > + > + For now, 32-bit mode is recommended, as 64-bit is still > + experimental and is missing a lot of features. > + > +config X86_RUN_32BIT > + bool "32-bit" > + help nits: "help" is not aligned > + Build U-Boot as a 32-bit binary with no SPL. This is the currently > + supported normal setup. U-Boot will stay in 32-bit mode even on > + 64-bit machines. When booting a 64-bit kernel, U-Boot will switch > + to 64-bit just before starting the kernel. Only the bottom 4GB of > + memory can be accessed through normal means, although > + arch_phys_memset() can be used for basic access to other memory. > + > +config X86_RUN_64BIT > + bool "64-bit" > + select X86_64 > + select SUPPORT_SPL > + select SPL > + select SPL_SEPARATE_BSS > + help > + Build U-Boot as a 64-bit binary with a 32-bit SPL. This is > + experimental and many features are missing. U-Boot SPL starts up, > + runs through the 16-bit and 32-bit init, then switches to 64-bit > + mode and jumps to U-Boot proper. > + > +endchoice > + > +config X86_64 > + bool > + > +config SPL_X86_64 > + bool > + depends on SPL > + > +choice > prompt "Mainboard vendor" > default VENDOR_EMULATION > > -- Regards, Bin _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
